Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography

The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study.     

Alemtuzumab (CAMPATH 1H) Induction Therapy in Cadaveric Kidney Transplantation—Efficacy and Safety at Five Years

Alemtuzumab is a powerful lymphocyte depleting antibody currently being evaluated in solid organ transplantation. This paper describes 5-year results of a single center study of alemtuzumab as induction in renal transplantation. Thirty-three renal transplant recipients received 20 mg alemtuzumab on day 0 and 1, followed by half-dose cyclosporin monotherapy (trough concentration 75-125 ng/mL) from day 3. They were compared in a retrospective contemporaneous-controlled manner with 66 kidney transplant recipients transplanted in the same period and center who received conventional immunosuppression with cyclosporin, azathioprine and prednisolone. In the alemtuzumab group 12% of recipients died compared to 17% in the control group (p = 0.48); likewise graft loss was similar in both groups (21% vs. 26%, respectively, p = 0.58). Incidence of acute rejection was also comparable at 5 years (31.5% vs. 33.6%), although the pattern of rejection was different with 14% patients in the alemtuzumab group experiencing rejection over 1 year post-transplant compared to none in the control group. There was no significant difference between groups in terms of infection or serious adverse events. While acknowledging the limitations of a relatively small single-center study, results suggest that alemtuzumab induction allowed satisfactory long-term patient and graft survival equivalent to that seen with standard triple immunosuppression, while avoiding steroid therapy.     

Maxillary sinusitis in adults: an evaluation of placebo-controlled double-blind trials

BACKGROUND: In general practice, acute sinusitis is frequently diagnosed and treated with antibiotics. OBJECTIVE: This study aimed to determine the evidence for the effectiveness of antibiotic treatment in acute maxillary sinusitis in adults by assessing the methodological quality of placebo-controlled double-blind randomized trials. METHOD: An evaluation by four raters through a 35-item scoring-scale for internal and external validity of all placebo-controlled double-blind randomized trials on acute sinusitis found between January 1966 and July 1996. RESULTS: Eighty-five trials were excluded because they were not placebo-controlled, double-blind, randomized, or were carried out in patients with chronic sinusitis or in children. The three remaining trials were performed in different populations (one in general practice) between 1973 and 1978. Only one study claimed superiority of antibiotic treatment. Different inclusion criteria and major outcome measures were used by the authors. The reliability of major outcome events was reported poorly or not at all and in two studies outcome measures were clinically inappropriate. The studies scored 30-62% of the maximum attainable score for internal validity and 10-20% for external validity. CONCLUSION: The effectiveness of antibiotic treatment in acute maxillary sinusitis in a general practice population is not based sufficiently on evidence.      

Management of venous stasis ulcer: long-term follow-up

In this study 112 patients (122 lower limbs) who had chronic venous stasis ulceration refractory to conservative management were treated surgically. Subfascial ligation was performed on 118 limbs and the long saphenous vein was removed in 4. Complications consisted of postoperative thrombophlebitis (2%), wound infection (2%) and wound infection with ulcer necrosis (1.5%). These all responded to conservative management. Follow-up (mean 7.9 years, median 11 years) showed a good or excellent result in 82% of cases, with healing of the ulcer and no ulcer recurrence despite significant noncompliance with support stockings. This paper is a long-term follow-up study of a surgical procedure for chronic venous stasis ulcers. The authors believe that the 82% good and excellent results may indicate that surgical intervention for refractory venous ulcers is a worthwhile procedure, providing potentially satisfactory long-term results.     

Bile salt-induced injury of rabbit oesophageal mucosa measured by hydrogen ion disappearance

Oesophageal injury secondary to gastro-oesophageal reflux is unlikely to be due to the effects of hydrochloric acid alone. The present authors have investigated the development of acid and bile salt-induced oesophageal mucosal injury in a rabbit model. Solutions of hydrochloric acid and sodium taurocholate (ST) were perfused through an isolated oesophageal preparation and mucosal injury was determined by measuring the rate of H+ disappearance. Perfusion with acid alone in concentrations up to 10 mmol/l did not affect the H+ disappearance rate. Addition of 1 mmol/l ST to an acid perfusate resulted in loss of H+ from the system. The increase in H+ disappearance rate was associated with loss of ST from the perfusate. Sodium taurocholate was only lost from the system when in an acid medium. Increased rate of H+ disappearance occurred even after the bile salt had been washed out of the perfused oesophagus. The mechanism of bile salt-induced mucosal injury was unlikely to be due to mucosal disruption secondary to micelle formation since the critical micellar concentration of taurocholate was found to be greater than that used in the perfusate. These findings indicate that bile salts may be an important factor in hydrochloric acid-related damage to oesophageal mucosa, by acting through mechanisms unrelated to micelle formation.